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Title: Effects of cement alkalinity, exposure conditions and steel-concrete interface on the time-to-corrosion and chloride threshold for reinforcing steel in concrete.
Creator: Nam, Jingak., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Effects of (1) cement alkalinity (low, normal and high), (2) exposure conditions (RH and temperature), (3) rebar surface condition (as-received versus cleaned) and (4) density and distribution of air voids at the steel-concrete interface on the chloride threshold and time-to-corrosion for reinforcing steel in concrete have been studied. Also, experiments were performed to evaluate effects of RH and temperature on the diffusion of chloride in concrete and develop a method for ex-situ pH...
Show moreEffects of (1) cement alkalinity (low, normal and high), (2) exposure conditions (RH and temperature), (3) rebar surface condition (as-received versus cleaned) and (4) density and distribution of air voids at the steel-concrete interface on the chloride threshold and time-to-corrosion for reinforcing steel in concrete have been studied. Also, experiments were performed to evaluate effects of RH and temperature on the diffusion of chloride in concrete and develop a method for ex-situ pH measurement of concrete pore water. Once specimens were fabricated and exposed to a corrosive chloride solution, various experimental techniques were employed to determine time-to-corrosion, chloride threshold, diffusion coefficient and void density along the rebar trace as well as pore water pH. Based upon the resultant data, several findings related to the above parameters have been obtained as summarized below. First, time for the corrosion initiation was longest for G109 concrete specimens with high alkalinity cement (HA). Also, chloride threshold increased with increasing time-to-corrosion and cement alkalinity. Consequently, the HA specimens exhibited the highest chloride threshold compared to low and normal alkalinity ones. Second, high temperature and temperature variations reduced time-to-corrosion of reinforcing steel in concrete since chloride diffusion was accelerated at higher temperature and possibly by temperature variations. The lowest chloride threshold values were found for outdoor exposed specimens suggesting that variation of RH or temperature (or both) facilitated rapid chloride diffusion. Third, an elevated time-to-corrosion and chloride threshold values were found for the wire brushed steel specimens compared to as-received ones. The higher ratio of [OH-]/[Fe n+] on the wire brushed steel surface compared to that of as-received case can be the possible cause because the higher ratio of this parameter enables the formation of a more protective passive film on the rebar. Fourth, voids at the steel-concrete interface facilitated passive film breakdown and onset of localized corrosion. This tendency for corrosion initiation increased in proportion to void size irrespective of specimen type. Also, [Cl -]th decreased with increasing void diameter. In addition, new ex-situ leaching method for determining concrete pore water alkalinity was developed.
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Date Issued: 2004
PURL: http://purl.flvc.org/fcla/dt/12096
Subject Headings: Reinforced concrete construction, Chlorides, Steel--Corrosion, Composite reinforced concrete
Format: Document (PDF)

Title: Atmospheric Corrosion Study of Weathering Steel Using Sensor Technology.
Creator: Hereng, Yann, Granata, Richard D., Florida Atlantic University
Abstract/Description: This research tests the corrosion resistance of weathering steel against carbon steel exposed to dry and humid cycles during laboratory experiments. Various environments are tested and include the following parameters: chloride concentration, pH and wetting time. Corrosion values from weight loss analysis are given and studied for the same environments. X-ray diffraction characterized the formation of different oxides as a function of the environment and gave a better understanding on the...
Show moreThis research tests the corrosion resistance of weathering steel against carbon steel exposed to dry and humid cycles during laboratory experiments. Various environments are tested and include the following parameters: chloride concentration, pH and wetting time. Corrosion values from weight loss analysis are given and studied for the same environments. X-ray diffraction characterized the formation of different oxides as a function of the environment and gave a better understanding on the formation of the protective patina on the weathering steel, and validated that chamber experiments reproduce field conditions. The study is supported by the design, test and validation of an easily deployable galvanic atmospheric corrosion sensor that allowed the monitoring of the corrosion rate on an hourly basis.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012526
Subject Headings: Steel, Structural--Corrosion, Reinforced concrete construction
Format: Document (PDF)

Title: Influence of pozzolanic admixtures on concrete pore water pH, chloride diffusion and chloride binding.
Creator: Charvin, Stephanie., Florida Atlantic University, Hartt, William H.
Abstract/Description: This report describes the results obtained from reinforced concrete slabs having different fly ash and silica fume content. The specimens are submitted to periodic seawater ponding. PH measurements as well as free and total chloride analyses were achieved at 1213 days in order to study the alkalinity, resistance to chloride ingress and binding properties afforded by each mix design. Water absorption experiments were also conducted at different relative humidities and in water. Pore water pH...
Show moreThis report describes the results obtained from reinforced concrete slabs having different fly ash and silica fume content. The specimens are submitted to periodic seawater ponding. PH measurements as well as free and total chloride analyses were achieved at 1213 days in order to study the alkalinity, resistance to chloride ingress and binding properties afforded by each mix design. Water absorption experiments were also conducted at different relative humidities and in water. Pore water pH was found to decrease with increasing admixture content and increasing relative humidity. The permeability to chloride ions was significantly reduced in the fly ash blends whereas most of the silica fume blends exhibited effective diffusion coefficients and chloride concentrations at the depth of steel marginally better than the controls. Both the fly ash and silica fume blends showed similar binding capacity at a given replacement ratio, the percentage of bound chloride increasing with increasing admixture content.
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Date Issued: 1999
PURL: http://purl.flvc.org/fcla/dt/15664
Subject Headings: Reinforced concrete construction--Corrosion, Concrete--Additives
Format: Document (PDF)

Title: Obstruction of chloride diffusion in concrete by embedded reinforcing bars.
Creator: Cros, Pascal., Florida Atlantic University, Hartt, William H.
Abstract/Description: A study was performed of the effect of reinforcing bars on chloride diffusion into concrete. These bars act as obstacles to chloride movement, and this obstruction allows the chloride concentration to build-up faster along the top of the reinforcing bar than elsewhere. As a consequence, the critical chloride threshold to initiate corrosion of the steel is reached sooner than otherwise expected. This research was performed using two different methods. First, chloride analyses were performed on...
Show moreA study was performed of the effect of reinforcing bars on chloride diffusion into concrete. These bars act as obstacles to chloride movement, and this obstruction allows the chloride concentration to build-up faster along the top of the reinforcing bar than elsewhere. As a consequence, the critical chloride threshold to initiate corrosion of the steel is reached sooner than otherwise expected. This research was performed using two different methods. First, chloride analyses were performed on chloride exposed concrete blocks by taking cores in the concrete and drillings along the trace of the top bars. Second, concrete blocks models were analyzed by finite element analysis and the effect of the obstruction by the bar quantified. The role of the reinforcing bar in the chloride diffusional flow is discussed considering these two methods.
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Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/13239
Subject Headings: Reinforcing bars--Corrosion, Reinforced concrete construction--Corrosion, Concrete--Additives, Chlorides--Diffusion rate
Format: Document (PDF)

Title: Concrete diffusivity and its correlation with chloride deposition rate on concrete exposed to marine environments.
Creator: Echevarria, Victor Anthony., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The aim of this study was to investigate the diffusion of chloride ions into concrete samples that were exposed in scenarios that simulate the splash, tidal, atmospheric, and immersed portions of a marine structure. To study the atmospheric deposition, the project also investigated the relationship between chloride ion deposition on the wet candle and its accumulation into concrete samples. Results from the wet candle experiment indicated that between 2% and 45% of the chlorides deposited per...
Show moreThe aim of this study was to investigate the diffusion of chloride ions into concrete samples that were exposed in scenarios that simulate the splash, tidal, atmospheric, and immersed portions of a marine structure. To study the atmospheric deposition, the project also investigated the relationship between chloride ion deposition on the wet candle and its accumulation into concrete samples. Results from the wet candle experiment indicated that between 2% and 45% of the chlorides deposited per square meter of exposed area could be found within the concrete samples. After 6 months, slag G1a blocks showed the most resistance to chloride penetration in the tidal and splash simulations. After 10 months of exposure, fly ash samples had the slowest rates of diffusion in the tidal simulation while the fly ash + silica fume samples and the slag samples measured similar rates of diffusion within the tidal zone. After 90 days of curing, cylinders composed of 20% fly ash & 8% silica fume measured the highest average resistivity values and were found to be less vulnerable to chloride ion penetration than the 20% fly ash and the 50% slag concrete through rapid migration tests.
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Date Issued: 2012
PURL: http://purl.flvc.org/FAU/3358557
Subject Headings: Reinforced concrete, Construction, Corrosion, Composite reinforced concrete, Corrosion, Testing, Concrete, Fluid dynamics, Concrete, Chemical resistance, Chlorides, Diffusion rate
Format: Document (PDF)

Title: Strength and durability of fly ash-based fiber-reinforced geopolymer concrete in a simulated marine environment.
Creator: Martinez Rivera, Francisco Javier, Sobhan, Khaled, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: This research is aimed at investigating the corrosion durability of polyolefin fiber-reinforced fly ash-based geopolymer structural concrete (hereafter referred to as GPC, in contradistinction to unreinforced geopolymer concrete referred to as simply geopolymer concrete), where cement is completely replaced by fly ash, that is activated by alkalis, sodium hydroxide and sodium silicate. The durability in a marine environment is tested through an electrochemical method for accelerated corrosion...
Show moreThis research is aimed at investigating the corrosion durability of polyolefin fiber-reinforced fly ash-based geopolymer structural concrete (hereafter referred to as GPC, in contradistinction to unreinforced geopolymer concrete referred to as simply geopolymer concrete), where cement is completely replaced by fly ash, that is activated by alkalis, sodium hydroxide and sodium silicate. The durability in a marine environment is tested through an electrochemical method for accelerated corrosion. The GPC achieved compressive strengths in excess of 6,000 psi. Fiber reinforced beams contained polyolefin fibers in the amounts of 0.1%, 0.3%, and 0.5% by volume. After being subjected to corrosion damage, the GPC beams were analyzed through a method of crack scoring, steel mass loss, and residual flexural strength testing. Fiber reinforced GPC beams showed greater resistance to corrosion damage with higher residual flexural strength. This makes GPC an attractive material for use in submerged marine structures.
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Date Issued: 2013
PURL: http://purl.flvc.org/fau/fd/FA0004037
Subject Headings: Concrete mixing -- Quality control, Green chemistry, Polymer composites, Reinforced concrete -- Corrosion -- Testing, Reinforced concrete construction
Format: Document (PDF)

Title: CRACKING OF CONCRETE DUE TO CORROSION OF VARIOUS EMBEDDED METALS.
Creator: TURNER, DEAN HUDSON., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The objective of this investigati.on was to contribute to the determination of a suitable metallic coating for steel reinforcement in concrete exposed to a marine environment and possibly to stray current. Concrete specimens embedded with steel, aluminum, cadmium, copper, molybdenum, nickel, and galvanized steel were exposed to sea water. Direct current was impressed on these to accelerate corrosion of the reinforcement so that cracking of the concrete could be observed within the time limit...
Show moreThe objective of this investigati.on was to contribute to the determination of a suitable metallic coating for steel reinforcement in concrete exposed to a marine environment and possibly to stray current. Concrete specimens embedded with steel, aluminum, cadmium, copper, molybdenum, nickel, and galvanized steel were exposed to sea water. Direct current was impressed on these to accelerate corrosion of the reinforcement so that cracking of the concrete could be observed within the time limit of the investigation. Aluminum, cadmium, copper, and nickel were found to have no beneficial effect on concrete cracking as compared to steel. In addition, no correlation between oxide-metal volume ratio and concrete time-to-cracking could be observed. It was found that corrosion of molybdenum has little or no tendency to crack concrete and its corrosion potential and active behavior approximates that of steel, indicating it may be an excellent coating.
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Date Issued: 1976
PURL: http://purl.flvc.org/fcla/dt/13820
Subject Headings: Reinforced concrete--Cracking, Underwater concrete construction, Reinforced concrete--Corrosion
Format: Document (PDF)

Title: Experimental and Modeling Study of Chloride Ingress into Concrete and Reinforcement Corrosion Initiation.
Creator: Yu, Hui, Hartt, William H., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Effects of reinforcement and coarse aggregate on chloride ingression into concrete and reinforcement corrosion initiation have been studied with experimental and modeling (finite element method) analyses. Once specimens were fabricated and exposed to a chloride solution, various experimental techniques were employed to determine the effect of reinforcement and coarse aggregate on time-to-corrosion and chloride ingress and concentration at corrosion locations. Model analyses were performed to...
Show moreEffects of reinforcement and coarse aggregate on chloride ingression into concrete and reinforcement corrosion initiation have been studied with experimental and modeling (finite element method) analyses. Once specimens were fabricated and exposed to a chloride solution, various experimental techniques were employed to determine the effect of reinforcement and coarse aggregate on time-to-corrosion and chloride ingress and concentration at corrosion locations. Model analyses were performed to verify and explain the experimental results. Based upon the results, it was determined that unexpectedly higher chloride concentrations were present on the top of the rebar trace than that to the side at the same depth and an inverse concentration gradient (increasing [Cl-] with increasing depth) occurred near the top of rebars. Also, coarse aggregate volume profile in close proximity to the rebar and spatial distribution of these aggregates, in conjunction with the physical obstruction afforded by reinforcement to chloride flow, complicates concrete sampling for Cl- intended to define the critical concentration of this species to initiate corrosion. Modeling analyses that considered cover thickness, chloride threshold concentration, reinforcement size and shape, and coarse aggregate type and percolation confirmed the experimental findings. The results, at least in part, account for the relatively wide spread in chloride corrosion threshold values reported in the literature and illustrate that more consistent chloride threshold concentrations can be acquired from mortar or paste specimens than from concrete ones.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012582
Subject Headings: Reinforced concrete construction--Corrosion, Chlorides--Diffusion rate, Composite reinforced concrete, Concrete--Chemical resistance
Format: Document (PDF)

Title: Corrosion initiation and propagation on corrosion resistant alloys embedded in concrete by accelerated chloride transport.
Creator: Gutierrez Tellez, Francisco., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Two duplex stainless steels rebars: UNS32304SS and UNS32101SS, were selected to investigate the corrosion initiation and propagation in reinforced concrete specimens. The investigation is divided in two phases with two different methods to accelerate the transport of chlorides through the concrete and initiate corrosion in a short period of time. After corrosion had initiated and propagated for some time; selected specimens were terminated for visual examination. On specimens selected for...
Show moreTwo duplex stainless steels rebars: UNS32304SS and UNS32101SS, were selected to investigate the corrosion initiation and propagation in reinforced concrete specimens. The investigation is divided in two phases with two different methods to accelerate the transport of chlorides through the concrete and initiate corrosion in a short period of time. After corrosion had initiated and propagated for some time; selected specimens were terminated for visual examination. On specimens selected for autopsy, the rebars in the top row showed corrosion to various degrees. Corrosion had propagated to such extent on the terminated specimens that the specimen showed cracks. Stray current might have caused accelerated corrosion on rebars where corrosion had initiated. Based on chloride concentrations measured at the rebar trace, corrosion initiated: on S32101 rebars on average at 7.9 kg/m3, and S32101 rebars on average at 6.0 kg/m3. The findings suggest that S32304 rebars corroded at a slower than S32101.
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Date Issued: 2013
PURL: http://purl.flvc.org/fcla/dt/3362380
Subject Headings: Concrete, Corrosion, Concrete construction, Reinforced concrete, Chemical resistance, Steel, Structural, Corrosion
Format: Document (PDF)

Title: Initiation and propagation of corrosion in dry-cast reinforced concrete ring specimens.
Creator: Seo, Bongjoon, Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The corrosion propagation stage of D-CRP (types F and C) was tested under immersion in water, high humidity, and covered with wet sand. The half-cell potential, linear polarization test, and electrochemical impedance spectroscopy measurements were performed. Selected specimens were terminated after 300 days of exposure and visually inspected. Based on corrosion potential measurements obtained during the corrosion propagation observation, and calculated corrosion rate based on LPR measurements...
Show moreThe corrosion propagation stage of D-CRP (types F and C) was tested under immersion in water, high humidity, and covered with wet sand. The half-cell potential, linear polarization test, and electrochemical impedance spectroscopy measurements were performed. Selected specimens were terminated after 300 days of exposure and visually inspected. Based on corrosion potential measurements obtained during the corrosion propagation observation, and calculated corrosion rate based on LPR measurements: all specimens were actively corroding. Additionally, EIS-Rc values were calculated for FS, CS and CH specimens. The Rc_EIS were generally greater than Rc_LPR values. EIS spectra for CI and FI specimens usually included mass transport limitations, as these specimens were immersed. Both type of specimens immersed in water (FI and CI), appeared to have higher corrosion rate based on LPR-Rc. However, upon autopsy it was revealed that a more modest amount of corrosion occurred on the reinforcing steel of FI and CI terminated specimens.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004226, http://purl.flvc.org/fau/fd/FA00004226
Subject Headings: Concrete -- Deterioration, Concrete construction, Corrosion and anti corrosives, Reinforced concrete -- Chemical resistance, Tubular steel structures -- Deterioration
Format: Document (PDF)

Title: Effect of Polarization on Steel Embedded in Simulated Piling Specimens Evaluated by Critical Chloride Threshold.
Creator: Tanner, Russell, Hartt, William H., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Critical chloride threshold, CT values for initiation of reinforced steel corrosion m mortar typical of Florida coastal bridge substructures were determined in laboratory tests. Previous research has reported CT values that vary by more than an order-of-magnitude, making design life estimation for structures difficult. On this basis, experiments on piling type specimens focused on [Cl-] contamination in the splash zone and coupling of this steel to a large surface area submerged anode. The...
Show moreCritical chloride threshold, CT values for initiation of reinforced steel corrosion m mortar typical of Florida coastal bridge substructures were determined in laboratory tests. Previous research has reported CT values that vary by more than an order-of-magnitude, making design life estimation for structures difficult. On this basis, experiments on piling type specimens focused on [Cl-] contamination in the splash zone and coupling of this steel to a large surface area submerged anode. The lower portion of simulated piling was immersed and the region above the waterline periodically sprayed with NaCI solution. Corrosion potential with respect to height above the waterline was monitored. A temporary depolarization method for determining as to whether or not corrosion had initiated is proposed. Chloride distribution at the reinforcement-concrete interface was determined in piling using energy dispersive x-ray analysis and related to height with respect to the waterline. Chloride threshold was related to corrosion potential.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012560
Subject Headings: Reinforced concrete construction, Steel, Structural--Corrosion, Chlorides, Corrosion and anti-corrosives, Seawater corrosion
Format: Document (PDF)

Title: Evaluation of Chloride Threshold for Steel Fiber Reinforced Concrete Composited in Aggressively Corrosive Environments.
Creator: Vogel, Dietrich H., Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Highway drainage pipes utilize concrete reinforced with steel wire to help mitigate water, earth, and traffic loads. Drainage pipes reinforced with zinc electroplated steel fibers offer a lower steel alternative to traditional steel wire cage reinforcements. The objective of the thesis research was to determine the physical and electrochemical characteristics of zinc electroplated steel fiber corrosion propagation. Experimental programs include: Fracture analysis of zinc electroplated steel...
Show moreHighway drainage pipes utilize concrete reinforced with steel wire to help mitigate water, earth, and traffic loads. Drainage pipes reinforced with zinc electroplated steel fibers offer a lower steel alternative to traditional steel wire cage reinforcements. The objective of the thesis research was to determine the physical and electrochemical characteristics of zinc electroplated steel fiber corrosion propagation. Experimental programs include: Fracture analysis of zinc electroplated steel fibers embedded in dry-cast concrete pipes exposed to varying chloride concentrations; Visual analysis of zinc electroplated steel fibers embedded in concrete exposed to varying chloride concentrations; Electrochemical analysis of zinc electroplated steel fibers embedded in concrete exposed to varying chlorides; Chloride threshold determination for zinc electroplated steel fibers immersed in simulated pore solution. Between the four experimental programs the most significant conclusion is that oxygen, moisture, and chlorides past the chloride threshold must be present for corrosion to propagate significantly on the zinc electroplated steel fibers.
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Date Issued: 2016
PURL: http://purl.flvc.org/fau/fd/FA00004637, http://purl.flvc.org/fau/fd/FA00004637
Subject Headings: Fiber-reinforced concrete--Cracking., Cement composites., Reinforced concrete construction., Reinforced concrete--Corrosion., Corrosion and anti-corrosives., Structural engineering.
Format: Document (PDF)

Title: Bulk diffusion of high performance concrete specimens exposed to different levels of sodium chloride and seawater.
Creator: Arias, Wendy J., Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The purpose of this study was to investigate the performance to chloride penetration of specimens made with three base compositions (three different supplementary cementitious materials) and water to cementitious ratios of 0.35, 0.41, or 0.47. The specimens were subjected to bulk diffusion test or full immersion. The mixes were exposed to 0.1 M, 0.6 M, or 2.8 M sodium chloride solution for different periods of time. Also, partially immersed specimens were exposed to indoor and outdoor...
Show moreThe purpose of this study was to investigate the performance to chloride penetration of specimens made with three base compositions (three different supplementary cementitious materials) and water to cementitious ratios of 0.35, 0.41, or 0.47. The specimens were subjected to bulk diffusion test or full immersion. The mixes were exposed to 0.1 M, 0.6 M, or 2.8 M sodium chloride solution for different periods of time. Also, partially immersed specimens were exposed to indoor and outdoor exposures (tidal, splash, barge). Chloride concentration profiles were obtained and the apparent diffusion coefficient was calculated. The skin effect was found only on some chloride profiles exposed to 0.1 M sodium chloride solution. The chloride binding capacity was calculated; specimens with 20% Fly Ash and 8% Silica Fume had the highest binding capacity (70.99%). The apparent diffusivity coefficient was found to be dependent on the curing regime as well as the water to cement ratio. The correlation between effective resistivity and apparent diffusion coefficient was determined.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004076, http://purl.flvc.org/fau/fd/FA00004076
Subject Headings: Bulk solids flow, Concrete -- Corrosion, Concrete, Effect of salt on, Reinforced concrete -- Deterioration, Sustainable construction
Format: Document (PDF)

Title: Chloride penetration into concrete structures exposed to the marine atmosphere.
Creator: Shill, Scott Thompson, Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Chloride ions present in the marine atmosphere contained in marine aerosols is investigated for a relationship with chloride that accumulated into concrete. Chloride profiles are conducted on several concrete mixes containing fly ash, silica fume, and slag, with water to cementitious ratios of 0.35, 0.41, and 0.47. The chloride accumulation in concrete samples exposed to the environment is investigated with relation to the chloride deposition from the marine atmosphere measured via the wet...
Show moreChloride ions present in the marine atmosphere contained in marine aerosols is investigated for a relationship with chloride that accumulated into concrete. Chloride profiles are conducted on several concrete mixes containing fly ash, silica fume, and slag, with water to cementitious ratios of 0.35, 0.41, and 0.47. The chloride accumulation in concrete samples exposed to the environment is investigated with relation to the chloride deposition from the marine atmosphere measured via the wet candle test. Results indicate a possible relationship for the total accumulated chloride in the concrete with the accumulated chloride deposition (wet candle). Over the exposure periods, concrete specimens with 50% slag addition and 0.47 w/cm had the lowest average rates of chloride accumulation for deposition under 100 g/m2day. Chloride accumulation was lower in concrete containing 20% fly ash and 8% silica fume with 0.35 w/cm for chloride deposition rates over 200 g/m2day.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004227, http://purl.flvc.org/fau/fd/FA00004227
Subject Headings: Chlorides -- Diffusion rate, Chlorides -- Environmental aspects, Concrete -- Chemical resistance, Concrete -- Permeability, Reinforced concrete -- Construction -- Corrosion
Format: Document (PDF)

Title: Durability testing of reinforced concrete beams under fatigue loading in a simulated marine environment.
Creator: Ahn, Woo-Suk., Florida Atlantic University, Reddy, Dronnadula V.
Abstract/Description: This thesis addresses the evaluation of the durability of reinforced concrete marine structures subjected to fatigue loading. The laboratory investigation was carried out on full and half size reinforced concrete specimens with three different water cement ratios (0.3, 0.4, and 0.56), static and fatigue loading conditions, and epoxy-coated and regular black steel reinforcements; a mineral admixture (silica fume), and a corrosion inhibitor (calcium nitrite) were used for specimens made with...
Show moreThis thesis addresses the evaluation of the durability of reinforced concrete marine structures subjected to fatigue loading. The laboratory investigation was carried out on full and half size reinforced concrete specimens with three different water cement ratios (0.3, 0.4, and 0.56), static and fatigue loading conditions, and epoxy-coated and regular black steel reinforcements; a mineral admixture (silica fume), and a corrosion inhibitor (calcium nitrite) were used for specimens made with water/cement ratio 0.4 concrete. The marine tidal zone was simulated by alternate filling and draining of the tank (wet and dry cycles), and a galvanostatic corrosion technique to accelerate corrosion of rebar was introduced. Half-cell potentials and changes of crack width were measured periodically during the exposure and followed by ultimate strength testing. The significant findings include adverse effect of fatigue loading, existence of an explicit size effect, poor performance of epoxy coated steel, and negative effect of the increasing water/cement ratio.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15178
Subject Headings: Concrete beams--Fatigue, Underwater concrete construction, Reinforced concrete--Fatigue, Seawater--Corrosion
Format: Document (PDF)

Title: Experimental evaluation of the durability of fly ash-based geopolymer concrete in the marine environment.
Creator: Edouard, Jean-Baptiste., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: The construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in...
Show moreThe construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in the way of producing concrete. However, to seriously consider geopolymer binders as an alternative to ordinary Portland cement, the durability of this new material should be evaluated in any comparative analysis. The main purpose of this study was to evaluate the durability characteristics of low calcium fly ash-based geopolymer concretes subjected to the marine environment, compared to ordinary Portland cement concrete with similar exposure. To achieve this goal, 8 molar geopolymer, 14 molar geopolymer and ordinary Portland cement concrete mixes were prepared and tested for exposure in seawater. Compressive strengths in the range of 2900 to 8700 psi (20-60 MPa) were obtained. The corrosion resistance performance of steel-reinforced concrete beams, made of these mixes, was also studied, using an accelerated electrochemical method, with submergence in salt water. The test results indicated that the geopolymer concrete showed excellent resistance to chloride attack, with longer time to corrosion cracking, compared to ordinary Portland cement concrete.
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Date Issued: 2011
PURL: http://purl.flvc.org/FAU/3170960
Subject Headings: Reinforced concrete, Corrosion, Testing, Reinforced concrete construction, Concrete, Mixing, Quality control, Environmental chemistry, Industrial applications, Polymer composites
Format: Document (PDF)

Title: Correlation of Chloride Diffusivity and Electrical Resistance for Cracked Concrete.
Creator: Merantus, Stanley W., Reddy, Dronnadula V., Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: The durability of Reinforced Concrete (RC) structures in the Marine environment is causing serious concern in the structural infrastructure. Reinforced concrete structures, exposed to aggressive environments, are expected to last with little or no maintenance for long periods of time. However, one of the most serious environmental exposures that causes degradation is Chloride Diffusion, due to shrinkage, atmospheric corrosion, and tide-induced wet and dry conditions at the air-water...
Show moreThe durability of Reinforced Concrete (RC) structures in the Marine environment is causing serious concern in the structural infrastructure. Reinforced concrete structures, exposed to aggressive environments, are expected to last with little or no maintenance for long periods of time. However, one of the most serious environmental exposures that causes degradation is Chloride Diffusion, due to shrinkage, atmospheric corrosion, and tide-induced wet and dry conditions at the air-water interfaces of coastal structures. Therefore, chloride diffusivity, which correlates with the electrical resistivity, has a significant impact on the durability of concrete. Concrete chloride diffusivity has been experimented by multiple agencies and researchers on sound concrete, but there is a considerable need for investigation of the durability of cracked concrete in the marine environment. The two test methods carried out are presented: Standardized American Society for Testing and Materials (ASTM) C1202 for Rapid Chloride Permeability (RCP) and ASTM D257 for Surface Resistivity (SR), and Nordtest (NT) Build 492 for Rapid Chloride Migration (RCM) and Bulk Resistivity (BR) for both sound (uncracked) and cracked (micro and macro) concrete. The limitations of the ASTM method, due to measurements before the steady-state migration is reached, does not account for leakage in cracked concrete, and the heating of the specimen due to higher current that increase the conductivity are indicated. The Rapid Chloride Migration test provides for the non-steady state of diffusion. Again, Bulk Resistivity, in contradistinction to Surface Resistivity is more accurate for cracked concrete. The correlation betweeen RCM-BR are plotted. Chloride Permeability/Migration is an important parameter that governs the Durability of Concrete. The principal contribution is the highlighting of the inadequacy of the current widely used standard ASTM C1202 for diffusivity testing, and the need for revision with further investigation.
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Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00004942, http://purl.flvc.org/fau/fd/FA00004942
Subject Headings: Reinforced concrete--Construction--Corrosion., Reinforced concrete--Deterioration., Concrete--Corrosion., Concrete--Chemical resistance., Chlorides--Environmental aspects., Chlorides--Diffusion rate.
Format: Document (PDF)

Title: Fatigue behavior of corrosion notched weathering steel samples.
Creator: Chen, Di, Granata, Richard D., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Weathering steel has been a primary construction material for bridges in the United States. Notches caused by corrosion are observed on the flange of steel I-beams. These notches reduce the cross section area of the structure and are threats to bridge safety. A606-04 Type 4 cold rolled weathering steel samples were studied in this thesis to understand the effect of notches that caused by corrosion. Weathering steel samples were in the shape of plates, which simulated flange of I-beams. The...
Show moreWeathering steel has been a primary construction material for bridges in the United States. Notches caused by corrosion are observed on the flange of steel I-beams. These notches reduce the cross section area of the structure and are threats to bridge safety. A606-04 Type 4 cold rolled weathering steel samples were studied in this thesis to understand the effect of notches that caused by corrosion. Weathering steel samples were in the shape of plates, which simulated flange of I-beams. The plate samples were notched across their surfaces by applying electrical current through an electrochemical circuit composed of an anode, a cathode and electrolyte. Sixteen samples were notched and cut into appropriate shape for fatigue testing. S-N (Stress-Number of cycles to failure) diagram established from fatigue data indicated that the fatigue strength decreased below AASHTO category B. Weibull analysis was also performed to understand the reliability distribution.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004092, http://purl.flvc.org/fau/fd/FA00004092
Subject Headings: Iron and steel bridges -- Corrosion, Protective coatings -- Evaluation, Reinforced concrete construction, Steel -- Fatigue, Steel, Structural -- Corrosion
Format: Document (PDF)

Title: Pitting potential of high performance duplex stainless steels reinforcements.
Creator: Sanchez, Erika Maria., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A cyclic polarization procedure was designed to evaluate the pitting potentials of high performance stainless steels in synthetic concrete pore water at different chloride concentrations. Cyclic polarization scans were performed on high performance stainless steel reinforcements, S32201, S32305 and S32205. Pitting initiation was observed below the oxygen evolution potential for high chloride concentrations. S32201 and S32304 showed the presence of metastable pitting before reaching its...
Show moreA cyclic polarization procedure was designed to evaluate the pitting potentials of high performance stainless steels in synthetic concrete pore water at different chloride concentrations. Cyclic polarization scans were performed on high performance stainless steel reinforcements, S32201, S32305 and S32205. Pitting initiation was observed below the oxygen evolution potential for high chloride concentrations. S32201 and S32304 showed the presence of metastable pitting before reaching its pitting potential. Pitting resistance performance, based on cyclic polarization, was consistent with each material's respective Pitting Resistance Equivalent Number (PREN) value. For S32201 and S32304, pitting potential decreased as the chloride concentration increased, whereas S32205 did not pit at the chloride concentrations tested.
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Date Issued: 2011
PURL: http://purl.flvc.org/FAU/3334100
Subject Headings: Reinforced concrete construction, Steel, Structural, Testing, Corrosion and anti-corrosives
Format: Document (PDF)

Title: Experimental Evaluation of the Structural Integrity of the Repairs for Corrosion-Damaged Marine Piles.
Creator: Bolivar, Juan Carlos, Reddy, Dronnadula V., Florida Atlantic University
Abstract/Description: Corrosion damage is the mam cause of deterioration for reinforced concrete marine structures. Given the current economic downturn, it has become increasingly important to repair existing structures with techniques that prolong their life-cycle. The process to identify suitable repairs is affected by the lack of a consistent methodology to predict the outcome of the repairs. This investigation intends to compare the performance of seven different repairs, in terms of corrosion resistance,...
Show moreCorrosion damage is the mam cause of deterioration for reinforced concrete marine structures. Given the current economic downturn, it has become increasingly important to repair existing structures with techniques that prolong their life-cycle. The process to identify suitable repairs is affected by the lack of a consistent methodology to predict the outcome of the repairs. This investigation intends to compare the performance of seven different repairs, in terms of corrosion resistance, structural integrity, and cost-effectiveness. Following initial exposure to corrosion, the specimens were repaired using the proposed techniques. They were then tested for durability under simulated tidal conditions with periodic corrosion monitoring. The structural integrity was evaluated by crack scoring and ultimate load testing, and a comprehensive evaluation matrix was prepared, to determine which repairs were most adequate for corrosion damage. The results of this investigation substantiate that the repairs including carbon wrapping, HDPE jacketing, and MMFX steel, outperformed the rest of the repairs.
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Date Issued: 2008
PURL: http://purl.flvc.org/fau/fd/FA00012506
Subject Headings: Reinforced concrete--Corrosion, Underwater concrete construction--Maintenance and repair, Materials--Deterioration--Prevention, Fibrous composites--Evaluation
Format: Document (PDF)

Reinforced concrete construction (7)	+ -
Chlorides (3)	+ -
Composite reinforced concrete (3)	+ -
Concrete (3)	+ -
Corrosion (3)	+ -

Reinforced concrete (3)	+ -
Reinforced concrete construction--Corrosion (3)	+ -
Testing (3)	+ -
Chemical resistance (2)	+ -
Chlorides--Diffusion rate (2)	+ -
Concrete construction (2)	+ -
Concrete--Additives (2)	+ -
Corrosion and anti-corrosives (2)	+ -
Polymer composites (2)	+ -
Reinforced concrete--Corrosion (2)	+ -
Steel, Structural (2)	+ -
Steel, Structural--Corrosion (2)	+ -
Underwater concrete construction (2)	+ -
Bulk solids flow (1)	+ -
Cement composites. (1)	+ -
Chlorides -- Diffusion rate (1)	+ -
Chlorides -- Environmental aspects (1)	+ -
Chlorides--Diffusion rate. (1)	+ -
Chlorides--Environmental aspects. (1)	+ -
Concrete -- Chemical resistance (1)	+ -
Concrete -- Corrosion (1)	+ -
Concrete -- Deterioration (1)	+ -
Concrete -- Permeability (1)	+ -
Concrete beams--Fatigue (1)	+ -
Concrete mixing -- Quality control (1)	+ -

College of Engineering and Computer Science (15)	+ -
Florida Atlantic University (15)	+ -
Department of Ocean and Mechanical Engineering (12)	+ -
Hartt, William H. (6)	+ -
Presuel-Moreno, Francisco (4)	+ -

Department of Civil, Environmental and Geomatics Engineering (3)	+ -
Reddy, Dronnadula V. (3)	+ -
Granata, Richard D. (2)	+ -
Ahn, Woo-Suk. (1)	+ -
Arias, Wendy J. (1)	+ -
Bolivar, Juan Carlos (1)	+ -
Charvin, Stephanie. (1)	+ -
Chen, Di (1)	+ -
Cros, Pascal. (1)	+ -
Echevarria, Victor Anthony. (1)	+ -
Edouard, Jean-Baptiste. (1)	+ -
Gutierrez Tellez, Francisco. (1)	+ -
Hereng, Yann (1)	+ -
Martinez Rivera, Francisco Javier (1)	+ -
Merantus, Stanley W. (1)	+ -
Nam, Jingak. (1)	+ -
Sanchez, Erika Maria. (1)	+ -
Seo, Bongjoon (1)	+ -
Shill, Scott Thompson (1)	+ -
Sobhan, Khaled (1)	+ -
TURNER, DEAN HUDSON. (1)	+ -
Tanner, Russell (1)	+ -
Vogel, Dietrich H. (1)	+ -
Yu, Hui (1)	+ -

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